Ignition appabatus



c. H. DAVIS, JR 1,967,079

IGNITION APPARATUS Original Filed Sept. 14, 1931 WWM mwfiwyy ww zz Patented July 17, 1934 1,967,079 IGNITION APPARATUS Anderson, Ind., assignor,

Charles Hall Davis, Jr.,

by mcsne assisnments,

notation, Detroit, Mich ware Application September 14, 1931, Serial No.

to General Motors Coracorporation of Dela- Renewed 30, 1932 Claims. (Cl. 123148) This invention relates to ignition apparatus for internal cycle engine and one-half engine speed for a two cycle engine.

One form of such ignition unit for firing an engine having an odd number of cylinders is lit disclosed in my copending application, Serial No. 562,655, filed Sept. 14, 1981. In my said applicaticn I provide an ignition unit employing an ignition timer having twice as many cam lobes as thereare engine cylinders and cooperating lid with a single circuit interrupter for controlling a single coil. As a means for distributing the sparking impulses I employ in said apparatus a distributor head having its distributor posts circumi'erentially arranged and cooperating with a so double-end dis 'ibutor rot'or whose arms extend diametrically in opposite directions.

It is the object of the present invention to provide an ignition apparatus of the type disclosed in my copending application but one db which is adapted to supply adequate ignition for an engine operating at a relatively high speed. In the disclosed embodiment of the present invention this aim is accomplished by providing two ignition coils controlled by two circuit into terrupters operated alternately by a cam whose lobes equal the number of engine cylinders. I preferably employ an ignition distributor having a head in which the distributor posts are. circumferentially arranged and a distributor rotor 35 having separate distributing segments extending diametrically in opposite directions, each segment being electrically connected with an ignition coil.

Further objects and advantages of the present invention will be apparent from the following (to description, reference being had to the accompanying drawing wherein a preferred embodiment of one form of the present invention is clearly shown.

In the drawing:

d5 The figure ofthe drawing is a wiring diagram illustrating the embodiment of the present invention.

' Referring to the drawing designates a shaft driven by the engine at one-half cycle speed,

t t namely, one-fourth engine speed for a four-cycle internal combustion engine or one-hair engine speed for a two-cycle internal combustion en gine. The shaft 20 drives a cam 21 having lobes equal in number to the engine cylinders, for 655 example, five lobes. The cam 20 cooperates alternately with rubbing blocks 22 and 32 attached respectively with springs 23 and 33 respectively to vers 2t and 34 which carry contacts 25 and respectively cooperating with grounded contacts 26 and '36. The spring ;2 3 urges the rubbing block 22 toward the cam 21 andthe contact 25 toward the contact 26 and is connected with terminal 27. Likewise spring conductor 33 urges rubbing block 32 toward cam 21 and contact 35 toward contact 36 and is connected with terminal 37. Condensers 28 and 38 are connected in parallel with pairs of contacts 25, 26 and 35, 36 respectively.

Terminals 27 and 37 are connected respectively with primary windings'Pl and P2 respectively of coils 29 and 39 and, these windings are connected by wires 30 and 40,with a switch 41 connected with battery 42 grounded at 43. v

The secondary coil S1 is connected by wire 44- with center terminal 45 of the head 46 of distributor which head also carries a ring 47 connected by wire 48 to secondary S2, and which carries a circular row of distributor posts 49. The distributor 50 includes a rotor block 51 carrying distributing arms R1 and R2 which are electrically connected respectively with center "terminal 45 and ring 47. These rotor arms R1 and R2 operate alternately to distribute the sparking impulses to the various cylinders of the engine.

In order that the bperation oithe present invention may be more clearly understood the posts 49 have each been marked with special indicia to indicate the number of the cylinder whose spark plug is connected to that post, to indicate which ignition coil secondary furnishes the sparking impulse ignition for that distributor post and which distributor rotor is eifective to distribute that sparking impulse to that distributor post. For instance,

it will be noted that there, are two sets of indicia applied to each post 49. one set not in brackets and the other set in brackets. The set of indicia not enclosed in brackets indicates conditions during one-half of a revolution of shaft 20, and the set of indicia enclosed in brackets indicates conditions during the other half of the revolution of the shaft 20. For example, in the indicia P1S1R1 applied to the uppermost post 49 in the drawing, the reference P1 means that that post isrpnnected to the spark plug of cylinder number 1. The reference S1 means that the sparking impulse is generated in secondary S1; and the reference "R1 designates that that sparking impulse is conducted by means of rotor arm R1. Similarly the 110 nr cu other indicia, not in brackets, as applied to the other posts 49 indicates the source of sparking impulse generation and the manner of distribution of that sparking impulse to the various spark plugs of the engine during the first half revolution of the shaft 20. The indicia enclosed in brackets, for example, indicia (P1--S2-R2) applied to the uppermost post 49 indicates that at a certain instant during the second half of the rotation of the shaft 20 the spark plug of the engine cylinder #1 is provided with a sparking impulse conducted from post Pi and generated in ignition coil secondary S2, and distributed by rotor R2. Similarly the other indicia enclosed in the brackets indicates the manner of sparking impulse generation and distribution during the second half of the rotation of the .shaft 20. It is therefore, apparent that by virtue of the construction and arrangement described, the present invention provides adequate ignition for a relatively high speed internal combustion engine having an odd number of engine cylinders. The present invention makes it possible to use a distributor head whose distributor posts will be circumferentially arranged, thereby presenting a pleasing external appearance.

It is apparent that the present invention may be applied to engine having odd numbers of cylinders other than the number shown in the drawing. For example, if the invention was applied to an engine having three cylinders instead of five, the number of lobes of cam 21 will be three and the distributor head will have three circumferentially arranged posts 49. The distributor rotor will have diametrically opposite arms R1 and R2 as before, connected respectively through a center contact and a ring contact with the separate secondary windings of two ignition coils.

From the foregoing description of the construction and mode of operation of ignition apparatus embodying the present invention, it will be noted that the present invention contemplates a distributor comprising a head having N posts arranged circularly and connected respectively with engine spark gaps, N being the number of explosion periods during an engine cycle, and a rotor carrying R (a plurality of) electrically separated conducting arms and operating at the rate of revolution during each engine cycle, said conductors moving past said posts, said conductors and posts being so arranged that the arms function alternately to distribute sparking impulses. Each time an arm moves adjacent to a post it is provided with a sparking impulse generated by R (a plurality of) sparking impulse generating devices connected respectively with the conducting arms, and operated alternately. It will be noted that those posts which are served by a certain arm during one engine cycle are served by a difierent arm during the next engine cycle. The means for operating thessparking impulse generating devices comprises. circui interrupter means having B circuit breakers operated by a cam having NXR cam lobes and rotated at the rate or revolution during each engine cycle, B equalling one or two.

While the form of embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted, all coming within the scope of the claims which follow.

What is claimed is as follows:

1. Ignition apparatus for an internal combustion engine having an odd number of cylinders, comprising in combination, a drive shaft operated by the engine at one-half engine cycle speed, a cam driven by the shaft and having lobes numerically equal to the number of cylinders, two circuit interrupters operated alternately by said cam, two ignition coils having their primary coils connected respectively with the interrupters, and a distributor head having a circular row of posts connectible with spark plugs and having a rotor carrying two electrically insulated rotor arms connected respectively with the secondary coils of said ignition coils, and operating alternately to distribute sparking impulses.

2. Ignition apparatus for internal combustion engines having N explosion periods during an engine cycle comprising, in combination, a distributor comprising a head having N posts arranged circularly and connected respectively with engine spark gaps, a rotor carrying R (a plurality of) electrically separated conducting arms and operating at the rate of revolution during each engine cycle, said conductors moving past said posts, said conductors and posts being so arranged that the arms function alternately to distribute sparking impulses, R sparking impulse generating devices connected respectively with the conducting arms, and means for operating said devices alternately.

3. Ignition apparatus for internal combustion engines having N explosion periods during an engine cycle comprising, in combination. a distributor comprising a head having N posts arranged circularly and connected respectively with engine spark gaps, a rotor carrying R (a plurality of) electrically separated conducting arms and operating at the rate of R revolution during each engine cycle, said conductors moving past said posts, said conductors and posts being so arranged that the arms function alternately to distribute sparking impulses and that those posts which are served by a certain arm during one engine cycle are served by another arm during the next engine cycle, R sparking impulse generating devices connected respectively with the conducting arms, and means for operating said devices alternately.

4. Ignition apparatus for internal combustion engines having N explosion periods during an engine cycle comprising, in combination, a distributor comprising a head having N posts arranged circularly and connected respectively with engine spark gaps, a rotor carrying 2 electrically separated conducting arms and operating at the rate or nitrevolution during each engine cycle, said conductors moving past said posts; said conductors and posts being so arranged that the arms function alternately to distribute sparking impulses and that those posts which are served by one arm during one engine cycle are served by the other arm during the next engine cycle, R sparking impulse generating devices connected respectively with the conducting arms, and means for operating said devices alternately.

5. Ignition apparatus for internal combustion engines having N explosion periods during an engine cycle, comprising in combination, a distributor comprising a head having N posts arranged circularly and connected respectively with engine spark gaps, a rotor carrying R (a plurality of) electrically separated conducting arms and operating at the rate of revolution during each engine cycle, said conductors moving past said posts, said conductors and posts being so arranged that the arms function alternately to distribute sparking impulses, R sparking impulse generating devices connected respectively with the conducting arms, and means for operating said devices alternately, said means comprising a circuit interrupting means having B circuit breakers operated by a cam having m B cam lobes and rotated at the rate of engine cycle, B equalling CHARLES HALL DAVIS, JR.

revolution during each one or two. 

